Method and system for junction termination in GaN materials using conductivity modulation

摘要

A semiconductor structure includes a GaN substrate having a first surface and a second surface opposing the first surface. The GaN substrate is characterized by a first conductivity type and a first dopant concentration. The semiconductor structure also includes a first GaN epitaxial layer of the first conductivity type coupled to the second surface of the GaN substrate and a second GaN epitaxial layer of a second conductivity type coupled to the first GaN epitaxial layer. The second GaN epitaxial layer includes an active device region, a first junction termination region characterized by an implantation region having a first implantation profile, and a second junction termination region characterized by an implantation region having a second implantation profile.

主权项

1. A method for fabricating a junction termination structure, the method comprising:
providing a substrate of a first conductivity type, the substrate having a first surface and a second surface; forming a first GaN epitaxial layer of the first conductivity type coupled to the first surface of the substrate; forming a second GaN epitaxial layer of a second conductivity type opposite to the first conductivity type, the second GaN epitaxial layer being coupled to the first GaN epitaxial layer; and after forming the second GaN epitaxial layer:
implanting ions into a first region of the second GaN epitaxial layer to form a first junction termination element characterized by a first conductivity less than a conductivity of the second GaN epitaxial layer; andimplanting ions into a second region of the second GaN epitaxial layer to form a second junction termination element characterized by a second conductivity less than the first conductivity.